First routed dovetails please critique

[Jeff Kerr]

Please give me your feedback. I bought a Rockler dovetail jig 3-4 years ago when I first got into woodworking. I was to much of a novice to understand how to set up the jig.

Well I have improved my skills some in the past couple of years and would like to make some dovetail drawer boxes to go with some shop cabinets I have completed.

These are from using scrap 3/4" ply to set up the jig. It did take a little while to set it up but I do think that I am getting the hang of it.

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Even though some of the ply split out I am happy with the joint itself. It seems pretty square

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Thoughts?

As far as the actual drawers, I have some 3/4" MDF in the shop and I thought of using it. I also have some 3/4" Orange Borg Chinese Birch ply as well. Does all ply tear out or is it because of the low grade scrap I used for setup?

Thanks for looking. As for now, I will make do with the Rockler jig. Half blinds are fine for now. Someday I will upgrade to one of the more feature rich jigs that are so highly spoke of here at SMC.

I can certainly fall back to some pocket screws if I don't get the hang of this. I have mastered the pocket screw jig :)

[Jim Becker]

Routing dovetails in plywood of any kind is not a forgiving act. You should also try your hand with solid stock.

3/4" MDF is going to make for some very, very heavy (weight wise) drawers, but they are not going to be as strong as plywood or solid stock will be with the same joinery.

[Tom Cowie]

Jeff

Whoa on the plywood it will eat your dovetail bits up and frustrate you with tearout and other issues in the process.

As Jim said try some dovetails with your jig on something like Poplar or Pine to start. This will get you some valuable experience with the jig and how it works.

I can't hardly make a poject without dovetails in it now. :)

good luck

Tom

[Joe Scharle]

I've got a $29.00 HF copy of that jig. It's as good as any, but the reason for the post is to point you to a great manual by

Woodstock Intl., Inc. D2796
It's on-line.

[Jeff Kerr]

Thanks for the comments. It makes sense that the ply will be harsh on the bit. I never thought of that. I was worried more about wasting good stock. :confused:


Joe thanks for the pointer on the manual. I'll go take a look.

[Joe Chritz]

I have had really good luck with a dovetail jig and Baltic birch plywood. Not so much with shop grade ply, however.

Use a backer board and go slow. Solid stock is more forgiving but you still need to be careful and deliberate in all moves.

Joe

[Jeff Kerr]

Thanks for all the great advice. I tried some pine stock. Looks like I need to fine tune the jig or the bit depth?

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[John Lucas]

I think your first DTs were very good. Yes, cutting DTs in plywood is difficult but not impossible. If you were cutting thru DTs, then use of a backer board would help. You were cutting half-blind so the one piece served as the backer...and you had tearout of the front piece. The only way to lessen that is to make your first cuts very gradual climb cuts...from right to left...against what they instructions might say. If you can have a real soft touch with early climb cuts, that will solve the initial tearout. Then, make the rest of the cut but dont "bully" it. Use less pressure to make the cut than more. Plywood will wear out router bits but if you are using a good router bit (CMT my preference), it will make it. Do keep the bit clean. After every session, use a bit cleaner and get rid of the burn marks onthe bit. Do that before you put the bit away for storage...otherwise the sap will erode the carbide...(seriously). Get a very fine diamond file and use it on the back side of the carbide...not the cutting edge.
Keep trying. With those first efforts, you will ahve perfect DTs in no time.

[Lee Schierer]

I learned a way to minimize tearout when cutting dovetails in plywood. I also have the Rockler jig. Instead of cutting the dovetails from left to right as the instructions say, cut them from right to left, also known as climb cutting. Make one pass straight across to score the wood and then go back and cut each individual pin by going int each finger on teh jig. This will pretty much elimnate the major chip out problems like you see in your photos. You can also apply a layer of regular (not painters type) maskign tape to the outside surfaces as the parts are mounted in the jig to further reduce tearout.

I also found that the climb cutting method also reduces burning in the dovetail slots and the bit runs much cooler.

For the safety consciuous people out there, climb cutting is easily done with a dovetail bit because of its small diameter it doesn't tend to pull the router quite as much as you would normally encounter when climb cutting with a router. Still you need to have a good grip on the router at all times.

[Eric Gustafson]

I cut through doves in 1/2 Baltic ply using a Porter Cable jig. In order to prevent delaminating the ply, I put pieces of 1/4 in. masonite as backer board for the front piece and same thickness stock for the back piece. Came out very good. I like that climbing cut right to left scoring suggestion and will try it the next go around.

[Joe Chritz]

If I remember correctly the Leigh jig instructions tell you to climb cut lightly first then finish in the "normal" orientation.

On the Leigh the tails underflush with the pins is set by the location of the "fingers" of the jig. The depth of cut only effects the fit of the pins.

There is a learning curve but now I use it for nearly all drawers.

Joe